Machinable Glass-ceramic vs. PTFE
Machinable glass-ceramic and PTFE belong to fundamentally different material chemistries. Machinable glass-ceramic is a ceramic material, while PTFE is polymeric. Therefore, their performance will be even more dissimilar than would be suggested by the difference in properties. There are 12 material properties with values for both materials. Properties with values for just one material (19, in this case) are not shown.
For each property being compared, the top bar is machinable glass-ceramic and the bottom bar is PTFE.
Metric UnitsUS Customary Units
Mechanical Properties
| Compressive (Crushing) Strength, MPa | 310 | |
| 6.9 to 24 |
| Flexural Strength, MPa | 96 | |
| 13 to 50 |
| Tensile Strength: Ultimate (UTS), MPa | 84 | |
| 13 to 25 |
Thermal Properties
| Maximum Temperature: Mechanical, °C | 760 | |
| 260 to 270 |
| Thermal Conductivity, W/m-K | 1.2 | |
| 0.24 to 0.65 |
| Thermal Expansion, µm/m-K | 21 | |
| 110 to 120 |
Electrical Properties
| Dielectric Constant (Relative Permittivity) At 1 MHz | 6.4 | |
| 2.1 to 2.4 |
| Electrical Dissipation At 1 MHz | 0.0050 | |
| 0.00017 to 0.050 |
| Electrical Resistivity Order of Magnitude, 10x Ω-m | 14 | |
| 2.0 to 18 |
Otherwise Unclassified Properties
| Density, g/cm3 | 2.7 | |
| 2.1 to 2.3 |
Common Calculations
| Strength to Weight: Axial, points | 8.8 | |
| 1.7 to 3.2 |
| Strength to Weight: Bending, points | 16 | |
| 5.7 to 8.7 |